Wheel drive unit for attachment to an aircraft running gear

ABSTRACT

Wheel drive unit for attachment to an aircraft running gear, said wheel drive unit including a drive motor or a drive motor with subsequent transmission and comprising the following features: (a) a mounting component adapted to be mounted to a supporting component of the aircraft running gear; (b) a coupling component releasably anchored to the mounting component in non-rotatable fashion; (c) the drive motor being supported by means of the coupling component such that the coupling component provides for torque support of the drive motor; (d) and a pluggable connection for connecting at least one pair of electric line sections and/or at least one pair of fluid line sections: (e) the torque output of the drive motor or of the subsequent transmission being adapted to establish a torque-transmitting connection to a wheel of the aircraft running gear when the wheel drive unit is attached to the aircraft running gear; (f) and the wheel drive unit—without the mounting component—, when the anchoring to the mounting component is released, being demountable from the aircraft running gear which also separates the two parts of the pluggable connection from each other.

BRIEF SUMMARY

One subject matter or embodiment of the invention is a wheel drive unitfor attachment to an aircraft running gear, said wheel drive unitincluding a drive motor or a drive motor with subsequent transmissionand comprising the following features:

(a) a mounting component adapted to be mounted to a supporting componentof the aircraft running gear on which supporting component at least onewheel of the aircraft running gear is supported so as to be rotatableabout the central axis of the supporting component;

(b) a coupling component releasably anchored to the mounting componentand non-rotatably fixed by engagement with the mounting component or thesupporting component of the aircraft running gear;

(c) the drive motor or the drive motor with subsequent transmissionbeing supported by means of the coupling component such that thecoupling component provides for torque support of the drive motor or ofthe drive motor with subsequent transmission;

(d) and a pluggable connection for connecting at least one pair ofelectric line sections and/or at least one pair of fluid line sections,a first part of the pluggable connection being associated with themounting component and a second part of the pluggable connection beingassociated with the coupling component;

(e) the torque output of the drive motor or of the subsequenttransmission being adapted to establish a torque-transmitting connectionto a wheel of the aircraft running gear when the wheel drive unit isattached to the aircraft running gear;

(f) and the wheel drive unit—without the mounting component —, when theanchoring to the mounting component is released, being demountable fromthe aircraft running gear which also separates the two parts of thepluggable connection from each other.

In more recent times, there are endeavors being made for developingwheel drive units for attachment to an aircraft undercarriage or runninggear. Such wheel drive units permit the aircraft or airplane to berollingly moved on the ground without being dependent on the propulsivepower of the aircraft engines. Typical examples are the “taxiing” of theaircraft on its way from the passenger terminal to the starting point ofthe runway, as well as “taxiing” of the aircraft after touchdown fromthe runway to the passenger terminal. By way of one or more wheel driveunits, an airplane on the ground can be rollingly moved in considerablymore energy-efficient manner than with the aid of the aircraft engine orengines.

Wheel drive units for attachment to an aircraft running gear should beas light as possible (in order to increase the own weight of theaircraft as little as possible) and should take as little space aspossible (in order to increase the space requirement of the aircraftrunning gear as little as possible or not at all). A wheel drive unitincluding a drive motor with subsequent transmission is favorable underthis aspect.

The term “(subsequent) transmission” used in the presentapplication/patent designates any type of torque transmission, eitherwithout a change of rotational speed, or with an increase or a reductionof rotational speed; a transmission with a reduction of rotational speedadvantageous in many cases. Transmissions having teethed wheels are agood solution in many cases.

The inventors of the present invention have endeavored to meet theobject of making available a wheel drive unit for attachment to anaircraft undercarriage or running gear, which requires as littlealterations as possible, or no alterations at all, to the aircraftrunning gear. The drive wheel drive unit meeting this object can beattached—by way of retrofitting—to the aircraft running gear in simplemanner. For attachment to new airplanes to be produced, it is necessaryat the most to effect minor changes to existing running gearconstructions, thus reducing the development costs and facilitatingpossibly necessary admission procedures.

The wheel drive unit according to one embodiment of the invention can beattached easily to an aircraft running gear by first attaching themounting component to the supporting component of the aircraft runninggear. The coupling component can be expediently anchored at this“anchoring point”, thus effecting a non-rotatable fixation of thecoupling component either by engagement with the mounting component orby engagement with the supporting component of the aircraft runninggear. The coupling component supports the drive motor or the drive motorwith the subsequent transmission such that the coupling componentprovides for torque support of the drive motor or the drive motor withsubsequent transmission. As regards the pluggable connection mentioned,a first part thereof is associated with the mounting component and asecond part thereof is associated with the coupling component, so thatthe pluggable connection is closed or established when the couplingcomponent is anchored to the mounting component, and the pluggableconnection is released when the coupling component is demounted from themounting component. When the wheel drive unit is attached to theaircraft running gear, there is a permanent or an interruptibletorque-transmitting connection between torque output of the drive motoror of the subsequent transmission to a wheel of the aircraft runninggear.

It is one of the significant advantages of the wheel drive unitaccording to one or more embodiments of the invention that the couplingcomponent along with the drive motor or drive motor with subsequenttransmission, respectively, can be demounted easily from the mountingcomponent and thus also from the aircraft running gear. As alreadymentioned, the two parts of the pluggable connection are separatedthereby as well. The demounting operation in its entirety can beperformed very rapidly, which in particular entails the advantage thatthe aircraft running gear wheel driven by the drive motor or the drivemotor with subsequent transmission can be changed almost within the sametime as in case of an aircraft running gear without wheel drive unit. Inview of the high wheel wear, wheels of aircraft running gears have to bereplaced relatively often. The ground time of an airplane always is tobe kept as short as possible as the flying airplane generates revenue,and not the airplane on the ground.

A further subject matter or embodiment of the invention is a wheel driveunit for attachment to an aircraft running gear, said wheel drive unitincluding a drive motor or a drive motor with subsequent transmissionand comprising the following features:

(a) a coupling component adapted to be mounted in non-rotatable fashionto a supporting component of the aircraft running gear on whichsupporting component at least one wheel of the aircraft running gear issupported so as to be rotatable about the central axis of the supportingcomponent;

(b) the drive motor or the drive motor with subsequent transmissionbeing releasably supported by means of the coupling component such thatthe coupling component provides for torque support of the drive motor orof the drive motor with subsequent transmission;

(c) and a pluggable connection for connecting at least one pair ofelectric line sections and/or at least one pair of fluid line sections,a first part of the pluggable connection being associated with thesupporting component of the aircraft running gear and a second part ofthe pluggable connection being associated with the coupling component;

(d) the torque output of the drive motor or of the subsequenttransmission being adapted to establish a torque-transmitting connectionto a wheel of the aircraft running gear when the wheel drive unit isattached to the aircraft running gear;

(e) and the wheel drive unit, by release of the mounted state of thecoupling component on the supporting component of the aircraft runninggear, being demountable from the aircraft running gear which alsoseparates the two parts of the pluggable connection from each other.

The wheel drive unit indicated in the preceding paragraph differs fromthe wheel drive unit indicated in the first paragraph of the descriptionin that it has no mounting component. It is suitable for such attachmentsituations in which the supporting component of the aircraft runninggear is designed to have the coupling component mounted thereto—so tospeak directly. The pluggable connection now is located between thecoupling component and the supporting component of the aircraft runninggear. As for the rest, the statements made hereinbefore in relation tothe wheel drive unit indicated in the first paragraph of thespecification are applicable again as regards the underlying object andthe advantages of the solution according to one embodiment of theinvention.

It is possible that the drive motor is an electric motor, in particularan electronically commutated electric motor composed with permanentmagnets, or a hydraulic motor or a compressed air motor. It is possibleto provide a planetary gear unit as subsequent transmission.

In the wheel drive unit according to the invention (according to thefirst subject matter of the invention or according to the furthersubject matter of the invention), which may contain one or, at the sametime, plural ones of the specific design features describedhereinbefore, the supporting component of the aircraft running gear mayhave the configuration of a hollow shaft. Such a hollow shaft can havethe mounting component, or the coupling component directly, mountedthereto in simple and expedient manner. Moreover, some of the existingaircraft running gears have one or several supporting components for oneor several wheels, having the configuration of a hollow shaft so that inso far only slight modifications of the supporting component arenecessary in order to make the same suitable for attachment of the wheeldrive unit.

In the wheel drive unit according to the invention (according to thefirst subject matter of the invention or according to the furthersubject matter of the invention), which may contain one or, at the sametime, plural ones of the specific design features describedhereinbefore, the non-rotatable connection between the couplingcomponent and the mounting component or between the coupling componentand the supporting component of the aircraft running gear may be aspline shaft connection. The term “spline shaft connection” in thepresent application is to comprise all kinds of connections affording inthe assembled state a non-rotatable fixation of the two connectionpartners relative to each other, but being releasable from each of theby way of axial relative movement of the two connection partners (whichis not cogently a purely axial relative movement or a movementcomprising solely the axial relative movement). The outline of thespline shaft connection visible in cross-section is of no particularrelevance. Typically it may be an outline similar to gear teeth or anoutline having a plurality of circumferentially distributed grooves, toname just two examples.

In the wheel drive unit according to the invention (according to thefirst subject matter of the invention), which may contain one or pluralones of the specific design features described hereinbefore, there maybe provided at least one mounting bolt extending from the outside of thewheel drive unit facing away from the mounting component to the oppositeoutside of the mounting component, with the drive motor or the drivemotor with subsequent transmission being clamped together with themounting component, sandwiching the coupling component therebetween, bymeans of the at least one mounting bolt. In particular, it is possibleto employ just one single, central mounting bolt, however, it is alsopossible to provide a plurality of mounting bolts, in particular incircumferentially distributed positions. The use of at least onemounting bolt, as described in the present paragraph, is alternativelypossible for anchoring the coupling component directly to the supportingcomponent of the aircraft running gear (wheel drive unit according tothe further subject matter of the invention).

In the wheel drive unit according to the invention (according to thefirst subject matter of the invention or according to the furthersubject matter of the invention), which may contain one or, at the sametime, plural ones of the specific design features describedhereinbefore, the pluggable connection may comprise one or, at the sametime, plural ones of the following features listed under (a) to (f)hereinbelow:

(a) The pluggable connection is designed to connect several pairs ofelectric power line sections for the electric motor;

(b) the pluggable connection is designed to connect at least two pairsof hydraulic line sections for the hydraulic motor or at least one pairof compressed air line sections for the compressed air motor;

(c) the pluggable connection is designed to connect at least one pair ofelectric signal line sections;

(d) the pluggable connection is designed to connect at least one pair offluid line sections for liquid or gaseous cooling fluid;

(e) at least one of the two parts of the pluggable connection isprovided with a shield for reducing electromagnetic radiation;

(f) the pluggable connection is designed as an integral overallpluggable connection comprising all terminals provided for the wheeldrive unit.

It can be seen that in situation (f), demounting of the couplingcomponent along with the drive motor or along with the drive motor andthe subsequent transmission can be accomplished in particularly simpleand rapid manner, especially when one wheel or several wheels of theaircraft running gear are to be changed or replaced.

When the pluggable connection comprises terminals for liquid or gas, atleast part of these terminals can be of self-closing design, i.e., uponseparation of the respective pluggable connection, the liquid or gasvolume present behind the terminal in the corresponding line can beclosed off with respect to the environment, so that there is no liquidor gas leakage—possibly apart from a slight initial amount—when thepluggable connection is separated.

When the pluggable connection comprises terminals for liquid or gas, atleast part of the terminals can be of self-venting design, i.e., minoramounts of air that have entered such terminals upon separation of thepluggable connection, upon subsequent mating of the pluggableconnection, are automatically vented to the environment and do notremain in the terminals and the adjoining line system, respectively.

Self-closing terminals or pluggable connections and self-ventingterminals or pluggable connections or line sections are known to theperson skilled in the art and available in the market, so that there isno need to describe the same in more detail here.

Express disclosure is herewith given to the effect that the inventivewheel drive unit (according to the first subject matter of the inventionor according to the further subject matter of the invention) can also bedesigned for attachment to another vehicle, which is not an airplane.Typical examples of such other vehicles are non-railbound land vehicles,such as trucks, buses and passenger vehicles. In that event, themounting component, or the coupling component directly, is designed forattachment to a chassis component of the non-railbound land vehicle(instead of to the supporting component of the aircraft running gear);the torque output of the drive motor or of the subsequent transmissionis adapted to establish a torque-transmitting connection to a wheel ofthe non-railbound land vehicle.

It is emphasized that it is possible with embodiments of the inventionto design a component that is present anyway in the wheel drive unit, inparticular a housing of the drive motor or of the transmission or ahousing of drive motor and transmission, at the same time as couplingcomponent. An example are means on said housing that permitnon-rotatable, positive or form-fit engagement with complementary meanson the mounting component or directly on the supporting component,respectively.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The invention will be described in more detail in the following by wayof exemplary embodiments shown in the drawings in partly schematicmanner. In the drawings:

FIG. 1 shows a wheel drive unit in the attached state in a sectionalview containing the central axis of the wheel drive unit, with part ofthe wheel drive unit being cut away;

FIG. 2 shows a wheel drive unit in the attached state in a sectionalview containing the central axis thereof;

FIG. 3 shows a further embodiment of a wheel drive unit in the attachedstate in a sectional view containing the central axis of the wheel driveunit, with part of the wheel drive unit being cut away;

FIG. 4 shows a first part of a pluggable connection in an enlargedscale; FIG. 5 shows a second part of a pluggable connection in anenlarged scale; FIG. 6 shows a further embodiment of the wheel driveunit in the attached state, partly in a sectional view containing thecentral axis of the wheel drive unit, with part of the wheel drive unitbeing cut away;

FIG. 7 shows the drive motor of the wheel drive unit of FIG. 6 in asectional end view according to arrow VII in FIG. 6;

FIG. 8 shows a further embodiment of a wheel drive unit in the attachedstate, partly in a sectional view containing the central axis of thewheel drive unit, with part of the wheel drive unit being cut away.

DETAILED DESCRIPTION

FIG. 1 is a schematic view. More in the left part of the drawing, therecan be seen a supporting component 2 of an aircraft running gear 4. Thesupporting component 2 has the configuration of a hollow tube ofconsiderable diameter, e.g., 15 to 40 cm. Only part of the aircraftrunning gear 4 is illustrated in the drawing. The suspension strut 6illustrated is mounted to the airplane above the illustration of FIG. 1.To the left of the suspension strut 6, there is present a secondsupporting component 2 in mirror symmetrical manner. Such aircraftrunning gears 4 can be found, e.g., as aircraft nose gear or centralgear below a wing of not too large airplanes.

The supporting component 2 illustrated rotatably supports a wheel 4 ofthe aircraft running gear 4, which holds for the left side (not shown)in mirror symmetrical manner as well.

A mounting component 10 is inserted into the supporting component 2 fromthe in FIG. 1 right-hand open face end of the supporting component 2.The mounting component 10 is in the form of a pot-shaped cylindricalsleeve having a radially outwardly projecting collar 12 at theright-hand end in FIG. 1. The bottom of sleeve 10 bears referencenumeral 13. The mounting component 10 is fixed to the supportingcomponent 2 both in non-rotatable and in axially fixed manner, e.g., bymeans of a nut, not shown, threaded onto the end portion of thesupporting component 2 and urging the collar 12 against the face end ofthe supporting component 2 via a shoulder.

A coupling component 14 engages with the mounting component 10. Thecoupling component 14 has a first cylindrical section 16 of smallerdiameter and a second cylindrical section 18 of larger diameter. Firstsection 16 is slidingly introduced into the interior of the mountingcomponent 10 and non-rotatably held in mounting component 10. Thisnon-rotatable fixation can be effected in particular by a spline shaftconnection between the outer circumference of the first section 16 andthe inner circumference of the mounting component 10. Anotherpossibility consists in providing several radially extending tongue andgroove engagements between the right-hand end face of collar 12 and ashoulder 20 of the coupling component 14 at the transition between thefirst section 16 and the second section 18.

At the outer circumference of the coupling component 14, specifically atthe outer circumference of the second section 18 and a cylindrical wallextended therefrom towards the left, there are attached a drive motor 22and a transmission 24. In the present embodiment, the drive motor 22 isa permanent-magnet electric motor. The electric motor 22 comprises ahousing 26, a radially outer stator 28 with windings on stator teeth,not shown, and a radially inner rotor 30 having the permanent magnetsdisposed on the outer circumference thereof. Rotor 30 is supported onthe outside of the coupling component 14. The timely activation anddeactivation of the stator windings and the power supply to the statorwindings are effected by electronic components.

Transmission 24 in the present embodiment is a planetary gear system. Ahollow shaft extends from the radially inner end portion of rotor 30through a partition 32 formed by motor housing 26, into the transmission24 and has its inner end portion formed as sun gear 34 of transmission24. Sun gear 34 meshes with a plurality of circumferentially distributedplanetary gears 36. Radially outside, the planetary gears 36 mesh withring gear teeth 38 formed on the inner circumference of the housing 40of transmission 24. The housing 40 of transmission 24 is constituted inpart by housing portions of the housing 26 of electric motor 22, namelyby the afore-mentioned partition 32 and a circumferential partition 42.On the left-hand side, transmission housing 40 is completed by a furtherwall 44.

The planetary gears 36 are all supported on a common planetary gearcarrier 46 so as to be rotatable about their own axis each. Theplanetary gear carrier 46 performs a revolving motion with a lower speedor number of revolutions than sun gear 34. The planetary gear carrier 46is supported on the outside of the coupling component 14. From theradially inner end portion of the planetary gear carrier 46, there is ahollow shaft 48 extending to the left through the wall 44 oftransmission 24 outwardly to a location near a component of wheel 8. Thelatter component is an externally splined ring 50 mounted on wheel 8.The left-hand end portion of hollow shaft 48 is provided with a splinedshaft section 52. An internally splined sliding bushing 54 is adapted tobe shifted between a right position, in which there is no engagementbetween sliding bushing 54 and ring 50, and a left position (illustratedin FIG. 1), in which the sliding bushing 54 is engaged both with thesplined shaft section 52 of the output hollow shaft 48 of transmission24 and with the splined shaft section of ring 50 and thus couples thewheel 8 with the rotational movement of hollow shaft 48. Sliding bushing54 in the present embodiment is connected to a tube-like actuatingmember 56 which in turn is mounted to the left-hand wall 44 oftransmission 24. The actuating member 56, at the left end thereof,projects into an outer circumferential groove of sliding bushing 54. Thetwo positions described of sliding bushing 54 can be obtained by axiallyshortening or extending the actuating member 56.

Between the mounting component 10 and the coupling component 14 there isestablished a pluggable connection 60, with a first part 62 thereofbeing mounted on the mounting component 10 and a second part 64 thereofbeing mounted on the coupling component 14. The first part 62 ispositioned adjacent the bottom 13 inside the mounting component 10. Thesecond part 64 is positioned at the left-hand end portion of couplingcomponent 14. In the assembled state shown in FIG. 1, the pluggableconnection 60 is closed, i.e., the line sections coming from the leftand terminating in first part 62 are connected to the line sectionscoming from the right and terminating in second part 64. However—as willstill be described in more detail further below—, when the couplingcomponent 14 along with drive motor 22 and transmission 24 is demountedfrom mounting component 10 and thus from the supporting component 2 inits entirety, the pluggable connection 60 is opened and theafore-mentioned line sections are separated from each other. Furtherdetails concerning the pluggable connection 60 and the line sectionswill be described further below. The line sections leading to first part62 are extended outwardly to the left through one or more openings inthe bottom 14 of mounting component 10. The line sections extending fromthe second part 64 extend to corresponding locations in drive motor 22or transmission 24, in particular to the windings of stator 28.

FIG. 1 reveals a central mounting bolt 66 extending through all of thecoupling component 14, the second part 64 of pluggable connection 60,the first part 62 of pluggable connection 60 and the bottom 13 ofmounting component 10. At both ends of mounting bolt 66, there areprovided threaded nuts 68; as an alternative, it is also possible toprovide an enlarged mounting bolt head at one end. When the right-handnut in FIG. 1 is released, the coupling component 14 together with drivemotor 22, transmission 24 and second part 64 of pluggable connection 60can be withdrawn/demounted towards the right from the mounting component10 and thus from the supporting component 2. In assembling these parts,nut 68 is tightened so that the coupling component 14 along with drivemotor 22 and transmission 24 is fixed to the mounting component 10 andthus to the supporting component 2 in total, inclusive of the describednon-rotatable fixation between coupling component 14 and mountingcomponent 10 and closure of the pluggable connection 60.

FIG. 2 illustrates a wheel drive unit 1, a supporting component 2 of anaircraft running gear and a wheel 8 of the aircraft running gear, whichare all designed quite similar to FIG. 1. However, the components shownin FIG. 2 are drawn more accurately and in the manner of a constructiondrawing. For ease of illustration, the drawing shows only few parts ofthe drive motor 22 and the transmission 24. The parts are shown in FIG.2 using the same numerals as those introduced in FIG. 1.

The further embodiment of a wheel drive unit 1 according to theinvention, as shown in FIG. 3, differs from the wheel drive unit 1 ofFIG. 1 in essence in the following aspects: There is no longer amounting component in the sense of the embodiment according to FIG. 1.Instead the supporting component 2 of the aircraft running gear 4, inits right-hand end portion of FIG. 3, is designed such that a couplingcomponent 14 can be mounted thereon. The first part 62 of pluggableconnection 60 is mounted in FIG. 3 in the right-hand end portion ofsupporting component 2. For mounting the coupling component 14 to thesupporting component 2, there are provided circumferentiallydistributed, axially extending bolts 70 (of which only the central axesare illustrated in FIG. 3). Bolts 70 are threaded to a radially inwardlyextending shoulder 72 of supporting component and are accessible fromthe right through corresponding openings in the right-hand end wall ofrotor 30 of drive motor 22. Instead of this design, a central bolt 66 asin FIGS. 1 and 2 could be provided. The right-hand end portion of thesupporting component 2 and the coupling component 14 (=central portionof the stator 28) are in non-rotatable engagement via a spline shaftconnection 15. The drive motor 22 is an electric motor in thisembodiment as well, with the statements made with respect to theembodiment of FIG. 1 concerning permanent magnets, windings, powersupply to the windings, time control of the winding currents, etc.,being applicable for the embodiment according to FIG. 3 as well.

Two further essential differences with respect to the embodiment of FIG.1 are that the drive motor 22 now has an outer rotor 30 and an innerstator 28 and that there is no transmission 24 present. The left-handend wall of rotor 30 is extended radially inside such that a splinedshaft section 52 is provided there which, by means of the slidingbushing 54, can be engaged with or disengaged from the ring 50 of wheel8 so as to establish or interrupt a torque-transmitting connectionbetween rotor 30 and wheel 8.

FIG. 4 shows an embodiment of a first part 62 of a pluggable connection60 in an enlarged view. The first part 62 of pluggable connection 60contains four groups of three plugs each for supplying electric power tothe windings of the stator 28 of the electric motor 22, two plugs 82 fortransmitting electric signals, two pluggable connection halves 84 forcoolant supply and coolant discharge. This first part 62 of pluggableconnection 60, as already described, is mounted on the mountingcomponent 10 (FIG. 1) or on the supporting component 2 (FIG. 3). Allnecessary lines 86 extend in a common enclosure 88 through suspensionstrut 6 or externally of suspension strut 6 into the aircraft.

FIG. 5 illustrates the design of the second part 64 of the pluggableconnection 60 in an end view. The view shows the pluggable connectionhalves 80 for electric power, the pluggable connection halves 82 forelectric signals and the pluggable connection halves 84 for coolant.

FIGS. 6 and 7 illustrate an embodiment in which the drive motorillustrated is a compressed air motor 100 instead of an electric motor.The example illustrated is a vane motor, with vane motors of theconstruction type illustrated existing both in the form of compressedair motors (operated by compressed air) and in the form of hydraulicmotors (operated by hydraulic liquid under considerable pressure).Comparing motors with the same output torque, hydraulic motors as a ruleare smaller than compressed air motors, as it is usually possible to usehydraulic liquid under higher pressure than in case of compressed airmotors. The type of construction illustrated is a vane motor; however,other construction types, e.g., toothed ring motor, crescent-type motor,radial piston motor, gear wheel motors can be chosen as well.

The sectional view of FIG. 7 illustrates the mode of operation of a vanemotor 100. A rotor 102 having a cylindrical main body carries, e.g.,five vanes 104 distributed across the circumference thereof, withsmaller and larger vane numbers being possible as well. The vanes 104are each plate-shaped and extend in axial direction of the rotor 102 onthe one hand and in radial direction on the other hand. The vanes 104are each seated in a complementary slot 106 of rotor 102 and are eachbiased radially outwardly by a spring 108. It is optionally possible, byway of a shoulder, not shown, on vane 104 and a counter-shoulder, notshown, in slot 106, to prevent the respective vane 104 from movingcompletely radially outwardly from the respective slot 106.

A housing 110 of vane motor 100 has an inner space 112 confined by awall 114 extending elliptically on the inside. Extending through thewall 114 are a supply channel 16 for compressed air, a main dischargechannel 118 for air and a posterior discharge channel 120 for air. Uponrotation of rotor 102 in clockwise direction in FIG. 7, the respectivespace 122 between two adjacent vanes 104 is increased from the supplychannel 116 to the main discharge channel 118. The expanding compressedair exerts pressure on the leading vane 104 that is preceding in thedirection of rotation of rotor 102. The posterior discharge channel 120serves to vent the respective space 122 as completely as possible beforenew compressed air enters through the supply channel 116.

The preceding description made reference to a compressed air motor. Asan alternative, there may also be provided a hydraulic motor. In case ofa hydraulic motor designed as a vane motor, the operational sequence isthe same, with the positioning of the supply and discharge channelsbeing possibly different. Compressed air motors and hydraulic motors ofthe construction types addressed here are known and available in themarket.

FIG. 6 shows—in more schematic manner as in FIG. 1—that there areprovided a mounting component 10 and a coupling component 14 as in caseof FIG. 1. The mounting component 10 is releasably mounted on thesupporting component 2 that it is fixed in relation to the supportingcomponent both in axial direction and in circumferential direction. Thecoupling component 14 is releasably mounted to the mounting component 10such that is fixed in relation to the mounting component 10 both inaxial direction and in circumferential direction. In the mounted stateof the coupling component 14, the pluggable connection 60 is in theconnecting state.

The housing of the compressed air motor 100 or of the hydraulic motor isconnected to the coupling component 14 such that the coupling component14, via the mounting component 10, provides for torque support of thecompressed air motor 100 or of the hydraulic motor.

It is emphasized that—as in changing from the embodiment according toFIG. 1 to the embodiment according to FIG. 3—the embodiment of FIGS. 6and 7 may be modified as well such that there is no mounting component10, and that the coupling component 14 is anchored to the supportingcomponent 2 directly in axially fixed and non-rotatable, but releasablemanner.

The embodiment according to FIGS. 6 and 7, analogously to theembodiments of FIGS. 1 and 3, has a sliding bushing 54 so that thesplined shaft section 52 of the output hollow shaft 48 of the compressedair motor 100 or of the hydraulic motor can be selectively coupled tothe ring 50 of wheel 8 in torque-transmitting manner, or be separatedfrom the same.

FIG. 8 illustrates an embodiment of a wheel drive unit 1 with compressedair motor 100 or hydraulic motor, in which a transmission 24 is providedbetween motor 100 and the output to wheel 8. This transmission is asingle-stage spur gear unit. The coupling component 14, without thepresence of a mounting component 10, is releasably mounted on thesupporting component 2. As regards the axially fixed and non-rotatableanchoring of the coupling component 14 to the supporting component 2 ofthe aircraft running gear, and also the sliding bearing 54, thestatements made hereinbefore in relation to the preceding embodimentsare applicable.

When the wheel drive unit according to one embodiment of the inventionis to be provided for attachment to a running gear or chassis componentof a non-railbound land vehicle, all statements concerning theembodiments made hereinbefore are applicable analogously. Instead of thesupporting component 2 of the aircraft running gear 6, a supportingcomponent of a chassis of a non-railbound vehicle will be present then.As with non-railbound vehicles, which are not airplanes, the wheel loadsas a rule are considerably lower than with airplanes, the supportingcomponent 2 typically will be dimensioned smaller.

The various embodiments described above can be combined to providefurther embodiments. In general, in the following claims, the terms usedshould not be construed to limit the claims to the specific embodimentsdisclosed in the specification and the claims, but should be construedto include all possible embodiments along with the full scope ofequivalents to which such claims are entitled. Accordingly, the claimsare not limited by the disclosure.

1. A wheel drive unit for attachment to an aircraft running gear, said wheel drive unit including a drive motor or a drive motor with subsequent transmission and comprising the following features: (a) a mounting component adapted to be mounted to a supporting component of the aircraft running gear on which supporting component at least one wheel of the aircraft running gear is supported so as to be rotatable about the central axis of the supporting component; (b) a coupling component releasably anchored to the mounting component and non-rotatably fixed by engagement with the mounting component or the supporting component of the aircraft running gear; (c) the drive motor or the drive motor with subsequent transmission being supported by means of the coupling component such that the coupling component provides for torque support of the drive motor or of the drive motor with subsequent transmission; (d) and a pluggable connection for connecting at least one pair of electric line sections and/or at least one pair of fluid line sections, a first part of the pluggable connection being associated with the mounting component and a second part of the pluggable connection being associated with the coupling component; (e) the torque output of the drive motor or of the subsequent transmission being adapted to establish a torque-transmitting connection to a wheel of the aircraft running gear when the wheel drive unit is attached to the aircraft running gear; (f) and the wheel drive unit—without the mounting component—when the anchoring to the mounting component is released, being demountable from the aircraft running gear which also separates the two parts of the pluggable connection from each other.
 2. A wheel drive unit for attachment to an aircraft running gear, said wheel drive unit including a drive motor or a drive motor with subsequent transmission and comprising the following features: (a) a coupling component adapted to be mounted in non-rotatable fashion to a supporting component of the aircraft running gear on which supporting component at least one wheel of the aircraft running gear is supported so as to be rotatable about the central axis of the supporting component; (b) the drive motor or the drive motor with subsequent transmission being releasably supported by means of the coupling component such that the coupling component provides for torque support of the drive motor or of the drive motor with subsequent transmission; (c) and a pluggable connection for connecting at least one pair of electric line sections and/or at least one pair of fluid line sections, a first part of the pluggable connection being associated with the supporting component of the aircraft running gear and a second part of the pluggable connection being associated with the coupling component; (d) the torque output of the drive motor or of the subsequent transmission being adapted to establish a torque-transmitting connection to a wheel of the aircraft running gear when the wheel drive unit is attached to the aircraft running gear; (e) and the wheel drive unit, by release of the mounted state of the coupling component on the supporting component of the aircraft running gear, being demountable from the aircraft running gear which also separates the two parts of the pluggable connection from each other.
 3. A wheel drive unit according to claim 1, wherein the drive motor is one of an electric motor, an electronically commutated electric motor composed with permanent magnets, a hydraulic motor, and a compressed air motor. 4-5. (canceled)
 6. A wheel drive unit according to claim 1, wherein the subsequent transmission is a planetary gear system.
 7. A wheel drive unit according to claim 1, wherein the supporting component of the aircraft running gear has the configuration of a hollow shaft.
 8. A wheel drive unit according to claim 1, wherein the non-rotatable fixation between the coupling component and the mounting component of the aircraft running gear is a spline shaft connection.
 9. A wheel drive unit according to claim 1, wherein at least one mounting bolt extending from the outside of the wheel drive unit facing away from the mounting component to the opposite outside of the mounting component, the drive motor or the drive motor with subsequent transmission being clamped together with the mounting component, sandwiching the coupling component therebetween, by means of the at least one mounting bolt.
 10. A wheel drive unit according to claim 3, wherein the pluggable connection is designed to connect plural pairs of electric power line sections for the electric motor or connect at least two pairs of hydraulic line sections for the hydraulic motor or at least one pair of compressed air line sections for the compressed air motor.
 11. (canceled)
 12. A wheel drive unit according to claim 1, wherein the pluggable connection is designed to connect at least one pair of electric signal line sections or connect at least one pair of fluid line sections for liquid or gaseous cooling fluid.
 13. (canceled)
 14. A wheel drive unit according to claim 1, wherein the pluggable connection comprises all terminals provided for the wheel drive unit.
 15. A wheel drive unit according to claim 1, wherein at least part of the terminals or line sections provided in the pluggable connection for liquid or gas is designed to be at least one of self-closing upon separation of the pluggable connection and self-venting.
 16. (canceled)
 17. A wheel drive unit according to claim 1, wherein at least one of the two parts of the pluggable connection is equipped with a shield for reducing electromagnetic radiation.
 18. A wheel drive unit according to claim 2, wherein the drive motor is one of a hydraulic motor, a compressed air motor, an electric motor, and an electronically commutated electric motor composed with permanent magnets.
 19. A wheel drive unit according to claim 2, wherein the subsequent transmission is a planetary gear system.
 20. A wheel drive unit according to claim 2, wherein the supporting component of the aircraft running gear has the configuration of a hollow shaft.
 21. A wheel drive unit according to claim 2, wherein the non-rotatable fixation between the coupling component and the supporting component of the aircraft running gear is a spline shaft connection.
 22. A wheel drive unit according to claim 13, wherein the pluggable connection is designed to connect plural pairs of electric power line sections for the electric motor, or to connect at least two pairs of hydraulic line sections for the hydraulic motor or at least one pair of compressed air line sections for the compressed air motor.
 23. A wheel drive unit according to claim 2, wherein the pluggable connection is designed to connect at least one pair of electric signal line sections or to connect at least one pair of fluid line sections for liquid or gaseous cooling fluid.
 24. A wheel drive unit according to claim 2, wherein the pluggable connection comprises all terminals provided for the wheel drive unit.
 25. A wheel drive unit according to claim 2, wherein at least part of the terminals or line sections provided in the pluggable connection for liquid or gas is designed to be at least one self-closing upon separation of the pluggable connection and self-venting.
 26. A wheel drive unit according to claim 2, wherein at least one of the two parts of the pluggable connection is equipped with a shield for reducing electromagnetic radiation. 